Dr Iryna, a medic in the city of Kharkiv, was given access on Sunday to shed more light on the Russian invasion.
The doctor, head of a regional perinatal centre, spent the day posting videos and photo detailing the tireless work the professionals are doing.
The superstar, 46, has more than 71 million followers on the social media platform.
The footage showed newborn babies being treated and a basement where patients have had to be moved to escape the bombings.
Dr Iryna said her work had been "24/7" since the illegal Russian invasion of the country.
"The first days were the most difficult. We had to learn how to work with bombings and strikes," she said.
"We are probably risking our lives but we don't think about it at all. We love our work. Doctors and nurses here, we worry, we cry but none of us will give up."
Speaking in a video on Instagram, the former midfielder said: "Hi everyone, so I’m handing over my social media to Iryna, the Head of the Regional Perinatal Centre in Kharkiv, Ukraine where she is helping pregnant mothers give birth safely.
"Thanks to your donations, the oxygen generators they have received are helping newborns survive in appalling conditions."
Becks took time out to encourage his followers around the world to donate to Unicef, the UN aid agency for which he serves as an ambassador.
David and wife Victoria are reported to have donated £1million to help fund the organisation's work in Ukraine.
He handed over his Instagram to the medic to show how deep the crisis is becoming.
Writing on Instagram Stories, the doctor went on: "On the first day of war, all pregnant women and mothers were evacuated to the basement. It was a terrible three hours that we spent together.
"Unfortunately, we can’t take babies who are in intensive care to the basement because they rely on life-saving equipment.
"Now. I’m not only the head of the centre but I continue to work as a paediatric anaesthesiologist. I unload cargo, work on logistics and offer emotional support."
She added: "UNICEF’s support is very important to us, They have been delivering supplies in Ukraine for years and they have good logistics to deliver ready-to-use kits to maternity hospitals."